A few days ago, I started our Gen III one evening, its first operation of the day. Outside air temp was mid 40s F. During the first 5 seconds or so after starting, it vibrated markedly, sounding as though it was firing on one cylinder. My son, who was standing immediately in front of the vehicle at the time, remarked, "Dad, are you trying to convert the Prius into a helicopter? It sounds like one." After a few seconds of this behavior, it smoothed out, and this behavior as not recurred. Has anyone else observed anything similar? Anyone wish to speculate about what might have happened?
Yes, this happened to me once and only lasted perhaps 5 to 10 seconds before it smoothed out. There are other posts about this issue. I thought it could be a misfire dealing with timing.
Take a look at this link for others with similar issues: http://priuschat.com/forums/gen-iii...troubleshooting/70128-rough-engine-start.html
